Addressing the Chartered Financial Analyst Society in Toronto, Mr Carney said that in major slumps: “To achieve a better path for the economy over time, a central bank may need to commit credibly to maintaining highly accommodative policy even after the economy and, potentially, inflation picks up.

“To ‘tie its hands’, a central bank could publicly announce precise numerical thresholds for inflation and unemployment that must be met before reducing stimulus.”

He added: “If yet further stimulus were required, the policy framework itself would likely have to be changed. For example, adopting a nominal GDP level target could in many respects be more powerful than employing thresholds under flexible inflation targeting.”